ROCK Sub-Frame

Contents:

• Legend
• Sub-Frames during the data aquisition
• Sub-Frames during the SynchR

Legend:

X	don't care
L	Lastbit - the last crate in a chain will have this asserted low
Sy	Is Low for SyncR frame in EFIFO only. Always High for DFIFO
Ca	Crate Address
CEOF	Chain End of Frame
SOF	Start of Frame
EOF	End of Frame
SLVADD	Slave address (1111 = near the ROCK)
SLVCHA	Slave Channel data
RES	Reserved

26	25	24	[23:20]	[19:13]	12	[11:0]
CEOF	SOF	EOF	SLVADD	SLVCHA	RES	DATA

A sub-frame is made of:

• a sub-header

  26	25	24	[23:20]	19	18	17	16	15	[14:12]	[11:0]
  1	0	1	0000	0	Sy	L	0	0	Ca	Trigger

• data from the slaves, starting from the slave with the higher address

  26	25	24	[23:20]	[19:13]	12	[11:0]
  1	1	1	SLVADD	SLVCHA	X	DATA

• a sub-footer

  26	25	24	[23:0]
  L	1	0	Parity including the sub-header

If no slave respond, an empty sub-frame is generated: (only in DFIFO)

26	25	24	[23:20]	19	18	17	16	15	[14:12]	[11:0]
L	0	0	0000	0	1	L	0	0	Ca	Trigger

This frame is not set to the CBUS.

Example:

sub-header

26	25	24	[23:20]	[19:13]	12	[11:0]
1	1	1	1010	Slv 10 Ch. Data	X	Slv 10 Data Word #1
1	1	1	1010	Slv 10 Ch. Data	X	...
1	1	1	1010	Slv 10 Ch. Data	X	Slv 10 Data Word #n
1	1	1	0010	Slv 2 Ch. Data	X	Slv 2 Data Word #1
1	1	1	0010	Slv 2 Ch. Data	X	...
1	1	1	0010	Slv 2 Ch. Data	X	Slv 2 Data Word #n

sub-footer

26	25	24	[23:20]	[19:12]	[11:0]
CEOF	SOF	EOF	SLVADD	RES	DATA

A sub-frame is made of:

• a sub-header

  26	25	24	[23:20]	19	18	17	16	15	[14:12]	[11:0]
  1	0	1	0000	0	Sy	L	0	0	Ca	GOLDENREF

• data from the slaves, starting from the slave with the higher address

  26	25	24	[23:20]	[19:12]	[11:0]
  1	1	1	SLVADD	X	SLVREF

• a sub-footer

  26	25	24	[23:0]
  L	1	0	Parity including the sub-header

Example:

sub-header

26	25	24	[23:20]	[19:12]	[11:0]
1	1	1	1010	X	LastTrigNr == GOLDENREF
1	1	1	0010	X	LastTrigNr == GOLDENREF

sub-footer